Cranks and Cranks no Start
I also took the throttle body off and cleaned it up real good, and took the iac off and cleaned... Seemed like it made it a little worse.. thats why i did the plugs wires and all that.. but still nothing..
so i checked the fuel pressure yesterday.
When it was cold it was at 0... turn key to on position with truck off and only read 10. Then when i started it took a bit and got up to 49.. Turned truck off went dropped down to 20 pretty quick then slowly went down after that...Does that mean my pump is bad or maybe my injectors are bad also?
When it was cold it was at 0... turn key to on position with truck off and only read 10. Then when i started it took a bit and got up to 49.. Turned truck off went dropped down to 20 pretty quick then slowly went down after that...Does that mean my pump is bad or maybe my injectors are bad also?
If you get 49 PSI with the engine running, that's where it is supposed to be. Pressure dropping off like that could be an injector sticking open, or, just a failed drainback valve in the pump/sending unit. All that does is give you slightly longer crank times when the engine is cold. (the valve.....) Bad injector would make it run rough...... but, I don't think it would 'get better' as the engine warmed up.
If you have a scan tool available to you, have a look at what the PCM thinks engine and IAT temps are when the engine is cold.
If you have a scan tool available to you, have a look at what the PCM thinks engine and IAT temps are when the engine is cold.
If the PCM is seeing the wrong temp, when in open loop, the engine will run like crap.
Need ALL of the sensor passing the correct information. It's a shot in the dark, but, does sorta fit with your symptoms....
Need ALL of the sensor passing the correct information. It's a shot in the dark, but, does sorta fit with your symptoms....
At key on engine off, the electric fuel pump should engage and get the fuel pressure up to 49PSI. If it's only getting to 10PSI, I'd start looking strongly at the fuel pump or the regulator on top of the pump. It could be that the regulator has failed and it allows the fuel pressure to drain right back down after the pump primes the fuel line. It sounds like that might be the case and the low fuel pressure is causing inadequate fuel in the cylinder to fire, and after a few tries you finally get enough going to fire the engine and keep it going. Once the engine is running, the fuel pump keeps pushing fuel and the fuel drain back is no longer a problem.
All fuel pumps are sold with a new regulator, but you can buy the regulator only and install it in an old pump. You have to pull the pump out of the tank and remove the regulator from it and reinstall everything.
If you have any doubts the pump is weak, replace the whole thing. It's not a fun job pulling the gas tank and spilling fuel.
All fuel pumps are sold with a new regulator, but you can buy the regulator only and install it in an old pump. You have to pull the pump out of the tank and remove the regulator from it and reinstall everything.
If you have any doubts the pump is weak, replace the whole thing. It's not a fun job pulling the gas tank and spilling fuel.
I will be replacing my pump shortly too.
I think I have two problems going on.







